2008年4月19日，田纳西州谢尔比县米林顿区域机场，"警惕卫士'2008"系列演习进行期间，美国陆军两架CH-47D直升机正在降落，被分配到伊利诺伊州空中国民警卫队。（Two U.S. Army CH-47 Chinook Helicopters, assigned to the Illinois National Guard arrive at Millington Regional Jetport in Millington, Tennessee, April 19, 2008, during Exercise Vigilant Guard 2008. Vigilant Guard is a series of training exercises to further enhance the preparedness of the National Guard to perform roles and responsibilities related to Homeland Defense and Military Support to Civil Authorities.）